Method and apparatus for generating target sounds

ABSTRACT

A method for headphone playback of target sound. Some of the bins of a sound file are accessed, wherein the sound file has several bins each bin storing a number of audio sections. Audio sections are selected from the accessed bins, and mixed while cross fading to form a target sound sequence. A headphone speaker is driven with the target sound sequence. Other aspects are also described and claimed.

This nonprovisional US patent application claims the benefit of theearlier filing date of U.S. provisional application No. 63/190,680 filedMay 19, 2021.

FIELD

As aspect of disclosure here relates to digital audio processingtechniques for improving the experience of headphone wearers. Otheraspects are also described.

BACKGROUND

Headphones are used not just for listening to music and participating inphone calls, but also for creating a quiet hearing experience for thewearer using acoustic noise cancellation for example while riding in anairplane, a train, or a bus. With designs that are increasinglycomfortable, and attractive yet unobtrusive, some headphones can also beworn for longer time periods. Wearers are often seen with headphones onnot just while engaged in other mental or physical activities but alsowhile simply relaxing.

SUMMARY

One aspect of the disclosure here is a process for generating a targetsound by a speaker that may be integrated within a headphone, that helpsavoid distractions from internal and external sound sources that alistener (e.g., the wearer of the headphone) might be hearing at anygiven moment. The target sound may mask or lessen the perceived loudnessof other sounds that the listener could be hearing and that aredistracting. The other sounds could be external such as passive leakageof environment sound (e.g., babble, chatter, machine noise) or it couldbe internal (something other than leakage of the environment sound thatthe listener hears, which may include occlusion effect, active real-timereproduction of environment sound, acoustic noise cancellationartifacts, media playback, and phone calls.) A result is that thelistener is able to focus on a particular activity they are engaged in,like reading or writing/typing, the listener is relaxed simply becausethe other sound which may not be desirable is being masked by the targetsound, the target sound helps the listener fall asleep, or the targetsound fills time intervals of no speech during podcasts or phone calls(e.g., like background.) These may enhance the listener's headphonelistening experience especially over a longer time interval of severalhours or for the most part of an entire day.

The above summary does not include an exhaustive list of all aspects ofthe present disclosure. It is contemplated that the disclosure includesall systems and methods that can be practiced from all suitablecombinations of the various aspects summarized above, as well as thosedisclosed in the Detailed Description below and particularly pointed outin the Claims section. Such combinations may have particular advantagesnot specifically recited in the above summary.

BRIEF DESCRIPTION OF THE DRAWINGS

Several aspects of the disclosure here are illustrated byway of exampleand not by way of limitation in the figures of the accompanying drawingsin which like references indicate similar elements. It should be notedthat references to “an” or “one” aspect in this disclosure are notnecessarily to the same aspect, and they mean at least one. Also, in theinterest of conciseness and reducing the total number of figures, agiven figure may be used to illustrate the features of more than oneaspect of the disclosure, and not all elements in the figure may berequired for a given aspect.

FIG. 1 shows an example apparatus for generating target sounds.

FIG. 2 shows an example graphical user interface that presents a targetsound user setting.

FIG. 3 illustrates a target sound sequence being formed from sections ofa sound file.

FIG. 4 is a flow diagram of an example method for generating the targetsound sequence.

FIG. 5 is a flow diagram of an example method for managing the playbackof the target sound sequence.

FIG. 6 depicts a decision processor that makes adjustments to includingmuting of the target sound sequence as a function of various variables.

FIG. 7 is a flow diagram of an example method for making adjustments tothe target sound sequence during its playback.

FIG. 8 is a flow diagram of another example method for makingadjustments to the target sound sequence during its playback.

DETAILED DESCRIPTION

Several aspects of the disclosure with reference to the appendeddrawings are now explained. Whenever the shapes, relative positions andother aspects of the parts described are not explicitly defined, thescope of the invention is not limited only to the parts shown, which aremeant merely for the purpose of illustration. Also, while numerousdetails are set forth, it is understood that some aspects of thedisclosure may be practiced without these details. In other instances,well-known circuits, structures, and techniques have not been shown indetail so as not to obscure the understanding of this description.

Everyday sounds can be distracting, discomforting, or overwhelming. Anaspect of the disclosure here is a process performed by an electroniccontrol device for generating target sound by a speaker (e.g., aheadphone speaker that is integrated into a housing of a headphone.)Target sounds may help reduce distractions and help a listener to focus,stay calm, or rest. Referring to FIG. 1, the process may be performed byan electronic control device 2 which may be for example a smartphone, asmartwatch, a laptop computer, a tablet computer or a desktop computer.The control device 2 may be a companion device (e.g., an audio sourceuser computing device) that is paired with one or more headphones (leftand right headphones 3) over a wireless communication link, e.g., aBluetooth link, or it may be communicatively coupled to the headphones 3over a wired or non-wireless link (e.g., a USB cable link.) In bothinstances, the control device 2 drives a target sound sequence as anaudio signal to the inputs of the speakers in the headphones 3. To drivea headphone speaker, a processor 7 or other hardware in the controldevice 2 conditions and prepares (formats for transmission or deliveryto a headphone speaker) an audio signal containing the target soundsequence. The audio signal that is driving the speaker may also containother audio content depending on the mode of operation of the controldevice 2, such as anti-noise from an acoustic noise cancellationsubsystem (ANC), media playback (e.g., from a music, movie, or podcastapp), phone call, or system sounds in a notification audio signal (suchas an incoming message alert, a calendar reminder, or a ringtone.) Theaudio signal is delivered to audio circuitry in the headphones 3. Therecan be different types of audio circuitry in the headphones 3 dependingon the capabilities of the headphones 3, ranging from passive, analogwired headphone speakers to a full-featured, wireless headphone that hasa built-in wireless transceiver, ANC, an external microphone used foractive reproduction of ambient environment sound, digital to analogconversion, and an audio amplifier whose load is the headphone speaker.Playback occurs when the audio circuitry feeds the audio signal to theinput of a headphone speaker to produce the target sound and optionallyother sound that is contained in the audio signal. While the figureshows the headphones 3 as being earbuds, they could instead be ofanother type such as over the ear headphones or on the ear headphones.

In FIG. 1, a display screen 4 of the control device 2 has beenconfigured by the processor 7 pursuant to instructions stored in memory6, e.g., as part of an operating system (OS) of the control device 2, todisplay one or more target sound user settings. The memory 6 is anexample of a non-transitory computer readable medium having instructionsthat configure a processor to perform most if not all of the methodoperations described in this disclosure. In the example shown, theprocessor configures the display screen 4 with a graphical userinterface (GUI) screen that presents several target sound user settings.The display screen 4 may be a touchscreen, in which the processor 7presents the GUI screen responding to a single finger swipe on thetouchscreen, for example during lock screen state or during home screenstate of the control device 2. In such a “quick view”, the touchscreenis configured to directly display a number commonly used controls whichincludes the target sound user setting and one or more typical settingssuch as a wireless local area network switch, screen brightness, volume,calculator, portrait orientation lock switch, flashlight, and camera.

The user settings permit a user (e.g., the listener, who may be wearingthe headphones 3 and who also owns or administers the control device 2)to manually control the target sound playback feature. There is a targetsound enable setting 10 which may be a toggle switch as shown thatenables and disables this feature. There may also be a sound typesetting 12 which be a selector switch that sets the type of sound forplayback (from a number of available types of sound files—see FIG. 2(e.g., waves or ocean, rainfall, stream, forest, birds, and asynthesized sound being a type of noise such as pink noise or whitenoise.) There is also a target sound user setting such as a firstselector 13 and optionally a second selector 14 that sets a target soundlevel parameter 16, which is stored within the memory 6. The processor 7generates the target sound sequence in accordance with one or more ofthese user settings (and the stored target sound level parameter 16 thatcorresponds to the user setting), and a speaker of the headphones 3 isthen driven with the generated target sound sequence.

The first selector 13 is a variable level setting that lets the user seta first one of the stored target sound level parameters 16 to between alow setting and high setting as shown, for example while the user islistening to the target sound playback through the headphones 3 they arewearing. In addition, or as an alternative to the first selector 13, thesecond selector 14 is a variable level setting that sets a second one ofthe stored target sound level parameters 16 (to between low and highsettings); the second selector 14 may be provided to set a differenttarget sound level during media playback (than during no mediaplayback.) In other words, if target sound is enabled, then its level isset during media playback according to the second one of the parameters16 and during no media playback it is set according to the first one ofthe parameters 16. The second selector 14 may indicate its level i) asbeing relative to a media playback level or ii) for use during mediaplayback. In another aspect of the disclosure here, the target sounduser setting includes a schedule setting to play the target soundsequence at certain times of the day or on certain days of the week.

Target Sound Design

Referring now to FIG. 3, this figure illustrates how the target soundsequence may be formed, using a sound file that is stored in the form ofN (being two or more) bins and several sections in each bin. As pointedout above, the sections that make up a sound file may be sounds ofrecorded nature (e.g., rain, a stream, waves, birds), or they may besynthetic (generated) sounds such as various type of noise. In oneaspect, the bins that make up a file are downloaded from the cloud andstored in “local” memory, within memory inside a headphone housing orwithin the control device 2 (see FIG. 1.) The file may be updateablefrom a remote serve (e.g., the cloud), in order for example use a moredesirable or a different version of the recorded or generated sound. Inone aspect, all of the sections in each bin may have the same length, orthere may be some that have different lengths (in terms of for examplesduration in milliseconds, ms.)

The processor 7 may execute an algorithm that organizes or defines asequence of bins from which it selects sections, which sections are thenjoined as shown to form the target sound sequence. The algorithm,including a predefined bin sequence may be pre-authored in thelaboratory and then downloaded into the control device for execution.The sections are mixed or linked while cross fading as needed to form asmooth, continuous playback sequence. Once the bin sequence has beenorganized, the processor 7 selectively pulls or downloads the bins (thatare called out in the bin sequence) from the server over time, togenerate the target sound sequence. This helps accommodate situationswhere computing resources are constrained, e.g., where the controldevice 2 or the memory inside the headphone housing is constrained. Inother words, a small preview of the target sound sequence is stored onthe control device or the headphone, but a larger story stays in theserver until it is time for that portion of the target sound sequence tobe generated for playback.

FIG. 4 shows a flow diagram of an example method for generating thetarget sound sequence. The process may begin with accessing (20) atleast part of a sound file, e.g., by learning the location in memory 6where some, not necessarily all, of the constituent bins of a givensound file are stored. Note that this may be preceded by downloadingthose bins from the cloud into the memory 6. Audio sections are thenselected from the accessed bins and mixed while cross fading (22), toform the target sound sequence (see FIG. 3.) In the case where, inoperations 20 and 22, the accessed sound file is recorded nature sounds,the audio sections are selected randomly from each bin. In the casewhere the accessed sound file is synthetically generated sounds (e.g.,noise), the selected audio sections in operation 22 may be longer (timeintervals) such as fifteen seconds each and may follow a deterministicsequence, e.g., a repeating loop. A level of the target sound sequencemay then be adjusted to match the stored, target sound level parameter(16), and then the headphone speaker is driven with the target soundsequence (23).

In one aspect, the recorded nature sounds in the bins are rainfallsounds, and for any given bin all of the sections in that bin sounddifferent but have similar rainfall intensity. In other words, multiplerainfall bins are selected where each has a different intensity ofrainfall. This lets the algorithm create a rainfall story by selectingsections from a low intensity bin (light rainfall) and then overtimeselecting sections from higher intensity bins (heavy downpour.) Forinstance, the target sound sequence begins a progression from lowintensity rainfall which then intensifies over time to high intensityrainfall, and wherein each time the target sound sequence startsplayback, this progression from low intensity rainfall to high intensityrainfall has a different speed. In this aspect, the algorithm is“dynamic” in that it creates a story, where rain starts as drops andthen intensifies overtime, with variations in this story each time thetarget sound feature starts to play. For instance, when the target soundfeature is enabled for the first time, the algorithm links the selectedbins to form intensifying rain over for example 15 minutes. The secondtime the target sound feature is enabled (or re-started following apause as described further below), the progression from slow to heavyrainfall takes foe example 5 minutes.

Still referring to FIG. 4, in one aspect that is illustrated, theselection of audio sections from the bins is in accordance with apre-authored or predefined bin sequence (24) from which the audioselections are made. Once the predefined bin sequence has ended or hasbeen completed (25), the predefined bin sequence (24) may be re-startedso that formation of the target sound sequence can continueuninterrupted, in operation 22. When each section in a bin has beenrandomly selected at least once (26), the sections of that bin areshuffled (27) before that bin is re-used in operation 22. In otherwords, the predefined bin sequence 24 may repeat but the selections fromeach bin in operation 22 are randomized, and each bin is shuffled everyso often.

Thus, as a whole, the resulting playback (of the target sound sequence)does not become memorable to the listener even over a period of weeks,months or years. For instance, the listener will not hear the same birdin the same place, or will not hear the same wave over and over again.This is in contrast to the random but still repetitive nature of awashing machine sound.

In another aspect, which also happens to be depicted in the same flowdiagram of FIG. 4, the method also includes stereo widening (28) of thetarget sound sequence before driving the left and right headphonespeakers (23). Doing so helps ensure that the target sound is perceivedby the listener as being wide or having an enhanced stereo effect, sothat the listener is less likely to focus on it. This may be done byscrambling or de-correlating left and right versions of the target soundsequence.

Control Device Operating System (OS) Infrastructure for Managing TargetSound Playback

As introduced earlier, the control device 2 may have an OSinfrastructure for managing target sound playback, through a GUI thatpresents user settings for controlling the target sound. These settingsmay include the enable setting 10 (see FIG. 1) that lets the listenermanually enable and disable playback of the target sound sequence. TheOS infrastructure may configure the processor 7 to perform the methoddepicted in FIG. 5 in which the enable setting 10 is accessed (31) todetermine whether or not target sound playback is enabled (33.) Iftarget sound playback is not enabled, then the processor automaticallyprompts a user of the control device 2 when media playback starts (35),to set the target sound level. If, however, target sound playback isenabled, then the processor automatically fades-in the target soundsequence, at a level that is in accordance with the target sound usersetting (36), in response to i) detecting that the user is wearingheadphones (37) or ii) detecting that media playback has started (39).

The flow diagram in FIG. 5 is also used to illustrate certain situationswhen the target sound playback is paused (40). To reduce powerconsumption, the algorithm that is generating the target sound sequence(e.g., part of the method in FIG. 4) may also be paused in that case. Inone aspect, the playback is paused in response to detecting that thelistener has removed one or both headphones 3 from their head (41). Inanother aspect, the playback is paused in response to detecting that theheadphones 3 are being used in a phone call (42), e.g., an audio orvideo call. In both instances, playback of the target sound sequence mayresume (by looping back to operation 36 as shown, which may also includere-starting the method in FIG. 4) once the headphones are back againstthe listener's head or the phone call has ended.

Dynamic Mixing of Target Sound with Other Audio Content

In one aspect, the target sound plays continuously while the headphones3 are being worn, and can mask unwanted environmental or external noisethat has leaked into the user's ear (despite the passive isolationprovided by wearing the headphones 3.) In addition, the processor 7 canbe configured to mix and duck the target sound sequence “under” othersimultaneous sound that is being reproduced by the headphone, and thatwould be heard by the listener. Ducking under refers to for examplereducing the wideband gain of the target sound sequence so that it isnot prominent from the listener's standpoint relative to other,simultaneously playing audio content. The other audio content may bemedia playback, system sounds (e.g., a message or calendarnotification), or active reproduction of ambient environment sound bythe headphone. In particular, the processor 7 could make gainadjustments on the target sound as a function of simultaneouslyoccurring active reproduction of environment sound or acoustic noisecancellation. For example, the target sound could be tailored(spectrally shaped) and added to mask any remaining or residual audibleeffects of an acoustic noise cancellation process.

FIG. 6 is a block diagram of how the target sound sequence can betailored before being combined with other audio signal content, to drivethe headphone speaker. This feature is also referred to here as dynamictarget audio. A decision processor (e.g., the processor 7 executing orconfigured by instructions stored in the memory 6) can adjust a widebandgain of the target sound sequence based on one or more of the followinginputs it could receive: detected ambient environment sound level;detected user context as being one of critical listening, running orjogging, or transportation as in a car or bus; detected environment ofthe listener as in office, home, or public transport; the current uservolume setting (a manual setting for overall sound volume that isdirectly based on for example the physical volume control buttons on asmartphone); detecting that media playback has started or stopped (e.g.,the media playback may be from a game app, a music app, a movie app, apodcast app, or a web browser); and detecting that a phone call hasstarted or ended. For instance, the wideband gain of the target soundsequence is decreased in response to media playback starting andincreased back up to the previous value (which is based on the storedtarget sound level parameter) when the media playback stops. In anotherinstance, the gain of the target sound sequence is decreased or thetarget sound sequence is muted in response to the call starting, andincreased or un-muted when the call ends. In yet another instance, thegain of the target sound is adjusted based on a personalizedhearing/audio profile that may, for example, be obtained through apersonalized enrollment process in which the user participates via theuser's control device 2 and headphones (by responding to questions aboutsound stimuli that are played back through the headphones the user iswearing.) More generally, the target sound sequence may be viewed asreplacing the listener's audible noise floor, but without interferingwith the listener's hearing of media playback (e.g., preserve speechintelligibility during media playback or during a phone call.)

In another aspect, the decision processor adjusts the gain of the targetsound sequence in such a way that reduces variation in short termloudness measurements of output by the headphone speaker despite changesin the other audio content. Short term loudness measurements aremeasurements of the headphone speaker output made over the past threeseconds. In other words, the decision processor keeps the overallloudness of the speaker output consistent or relatively constant despitechanges in the target sound sequence and changes in the other user audiocontent (that is simultaneously being played back.)

In another aspect, the processor 7 is configured to automatically duckthe target playback in response to certain types of apps being launchedor running, such as games, music, and movie apps, but continues thetarget playback without ducking (or ducks less) when the user audiocontent that is being routed to the headphone speaker is from a podcastapp or a web browser. Such a method for playback of target sound mayproceed as follows, referring now to the flow diagram of FIG. 7. Thetarget sound sequence is generated in accordance with a user setting(43), and a headphone speaker is driven with the target sound sequence(44). When a request for playback is detected from a first app type orfrom a second app type (45), the processor 7 continues to drive theheadphone speaker with the target sound sequence while combining thetarget sound sequence with playback from the first app type (48) or fromthe second app type (47). When combining with playback from the firstapp, the processor automatically ducks the target sound sequence (50),but when combining with playback from the second app, the processor willeither i) not duck the target gain sequence, or ii) duck the target gainsequence less than when ducking during playback from the first app type(51).

In another aspect, when target sound is being played and no other useraudio from an app is being routed to the headphone speaker, theprocessor may automatically reduce the gain of the target sound sequencewhen a podcast app starts to play but then raises the gain (back to alevel that is in accordance with the stored target sound level parameter16) when the podcasts app stops playing.

Referring now to FIG. 8, this is a flow diagram of another method fordynamic headphone playback of target sound, in which the target soundsequence is being generated as above in accordance with a user setting(43) and is driving the headphone speaker (44). While doing so, theprocessor makes automatic adjustments to the target sound sequence (55)as a function of the time day or as a function of ambient environmentlight levels (53). Such adjustments are not limited to wideband gainadjustments, but instead or in addition may include spectral shaping orother digital audio DSP adjustments—see, e.g., FIG. 6. For instance, thetarget sound sequence may be adjusted to produce brighter sound in themorning or during daylight, than in the evening or at nighttime.

The following statements may also be made concerning the various aspectsdisclosed above.

Operating System Infrastructure for Controlling Target Sound Playback

1. A method for controlling target sound playback, the methodcomprising: configuring a display screen of a control device to displaya target sound user setting for controlling target sound playback,wherein the target sound user setting controls a stored target soundlevel parameter that is stored within memory of the control device;generating a target sound sequence in accordance with the user setting;and driving a speaker with the target sound sequence.

1a. The method of statement 1 wherein the target sound playback of thetarget sound sequence enables a listener to avoid distractions frominternal sound sources or external sound sources that the listener hearssimultaneously with the target sound playback.

1b. The method of statement 1 wherein the target sound playback of thetarget sound sequence masks or lessens perceived loudness of othersounds that a listener is hearing.

1c. The method of statement 1 wherein the target sound playback of thetarget sound sequence enables a listener to focus on a particularactivity in which the listener is engaged.

2. The method of statement 1 wherein the target sound user settingcomprises a variable level setting, separate from a user volume settingof the control device, that sets the stored target sound levelparameter.

3. The method of statement 2 wherein the variable level settingindicates a level i) as being relative to a media playback level or ii)for use during media playback.

4. The method of statement 2 further comprising configuring the displayscreen to display a further target sound user setting having a furthervariable level setting that sets a further stored target sound levelparameter that is used only during media playback or during a phonecall.

5. The method of anyone of statements 1-4 wherein the target sound usersetting comprises a schedule setting to play the target sound sequenceat certain times of the day or on certain days of the week.

6. The method of anyone of statements 1-5 wherein the target sound usersetting comprises a sound type setting.

7. The method of statement 6 wherein the sound type setting indicates atleast one of: waves or ocean, rainfall, stream, forest, birds, and asynthesized sound being a type of noise such as pink noise or whitenoise.

8. The method of anyone of statements 1-7 wherein the display screen isa touchscreen, and configuring the display screen to display the usersetting comprises responding to a single finger swipe on the touchscreenduring lock screen state or during home screen state, by directlydisplaying a plurality of commonly used controls which includes thetarget sound user setting and one or more of: a wireless local areanetwork switch, screen brightness, volume, calculator, portraitorientation lock switch, flashlight, and camera.

9. The method of any one of statements 1-8 further comprising if targetsound playback is not enabled, then automatically present a prompt viathe control device or via a headphone when media playback starts, to seta target sound level.

10. The method of anyone of statements 1-9 further comprising if targetsound playback is enabled, then automatically fade-in the target soundsequence at a level that is in accordance with the target sound usersetting and in response to detecting that i) the user is wearing one ormore headphones or ii) media playback has started.

11. The method of anyone of statements 1-10 further comprisingcontinuously driving the speaker with the target sound sequence until i)detecting that a headphone having the speaker has been removed from auser's ears or ii) detecting that the headphone having the speaker isbeing used in a phone call, and in response reducing gain of the targetsound sequence or pausing playback of the target sound sequence.

11a. The method of any one of statements 1-10 wherein the target soundsequence continuously drives the speaker without any gain reductionwhile a system notification audio signal such as a message alert, acalendar reminder, or a ringtone is also simultaneously driving thespeaker.

11b. The method of statement 11a wherein the target sound sequence isgain reduced but not muted, while the system notification audio signalis also driving the speaker.

12. The method of statement 11 wherein the gain of the target soundsequence that is driving the speaker is reduced during the phone calland is then raised in accordance with the target sound user setting whenthe phone call has ended.

13. A non-transitory computer readable medium comprising instructionsthat configure a processor to: configure a display screen of a controldevice to display a target sound user setting for controlling targetsound playback, wherein the target sound user setting controls a storedtarget sound level parameter that is stored within memory of the controldevice; and generate a target sound sequence in accordance with the usersetting, wherein the target sound sequence is to drive a speaker.

14. The computer readable medium of statement 13 wherein the targetsound user setting comprises a variable level setting that sets thestored target sound level parameter.

15. The computer readable medium of statement 14 wherein the variablelevel setting indicates a level i) as being relative to a media playbacklevel or ii) for use during media playback.

16. The computer readable medium of statement 14 wherein the processoris further configured to configure the display screen to display afurther target sound user setting having a further variable levelsetting that sets a further stored target sound level parameter that isused only during media playback or during a phone call.

17. The computer readable medium of statement 13 wherein the targetsound user setting comprises a schedule setting to specify playback ofthe target sound sequence at certain times of the day or on certain daysof the week.

18. The computer readable medium of anyone of statements 13-17 whereinthe display screen is a touchscreen, and configuring the display screento display the user setting comprises responding to a single fingerswipe on the touchscreen during lock screen state or during home screenstate, by directly displaying a plurality of commonly used controlswhich includes the target sound user setting and one or more of: awireless local area network switch, screen brightness, volume,calculator, portrait orientation lock switch, flashlight, and camera.

19. The computer readable medium of anyone of statements 13-18 whereinthe processor is configured to if target sound playback is not enabled,then automatically prompt, via the control device or via a headphone inwhich the speaker is integrated, when media playback starts, to setatarget sound level.

20. The computer readable medium of any one of statements 13-19 asintegrated into the control device along with the processor.

21. The computer readable medium of statement 20 wherein the controldevice is a smartphone, a smartwatch, a laptop computer, a tabletcomputer or a desktop computer.

The following statements may also be made concerning the various aspectsdisclosed above.

Dynamic Target Audio

1. A method for dynamic playback of target sound, the method comprising:generating a target sound sequence in accordance with a user setting;driving a speaker with the target sound sequence; and adjusting a gainof the target sound sequence based on one or more of the following:detecting an ambient environment sound level; detecting a user contextas being one of critical listening, running or jogging, ortransportation as in a car or bus; detecting an environment of a user asin office, home, or public transport; detecting a user volume setting;and detecting that media playback has started or stopped.

1a. The method of statement 1 wherein the target sound sequence enablesa listener to avoid distractions from internal sound sources or externalsound sources that the listener hears simultaneously with playback ofthe target sound sequence.

1b. The method of statement 1 wherein the target sound sequence masks orlessens perceived loudness other sounds that a listener is hearing.

1c. The method of statement 1 wherein the target sound sequence enablesa listener to focus on a particular activity in which the listener isengaged.

2. The method of statement 1 wherein adjusting the gain of the targetsound sequence is based on detecting the user volume setting, whereinthe gain is increased in response to the user volume setting beingraised, and decreased when the user volume setting is lowered.

3. The method of any one of statements 1-2 further comprising drivingthe speaker with other audio content combined with the target soundsequence.

4. The method of statement 3 wherein the other audio content is frommedia playback, wherein adjusting the gain of the target sound sequenceis based on detecting that the media playback has started, wherein thegain is decreased in response to media playback starting and increasedwhen the media playback stops.

5. The method of statement 4 wherein the media playback is from one of:a game app, a music app, a movie app, a podcast app, or a web browser.

6. The method of anyone of statements 4-5 wherein the gain is decreasedbut not muted.

7. The method of statement 3 wherein the other audio content is from aphone call, wherein adjusting the gain of the target sound sequence isbased on detecting that the phone call has started, wherein the gain isdecreased or the target sound sequence is muted in response to the phonecall starting, and increased or un-muted when the phone call ends.

8. The method of statement 3 wherein adjusting the gain of the targetsound sequence reduces variation in short term loudness measurements ofoutput by the speaker despite changes in the other audio content.

9. The method of statement 8 wherein short term loudness measurementsare measurements over the past three seconds.

10. A method for playback of target sound, the method comprising:generating a target sound sequence in accordance with a user setting;driving a speaker with the target sound sequence; and when detecting arequest for playback from a first app type or from a second app type,continuing to drive the speaker with the target sound sequence combinedwith playback from the first app type or from the second app type, whencombined with playback from the first app, automatically ducking thetarget sound sequence, and when combined with playback from the secondapp, either i) not ducking the target gain sequence, or ii) ducking thetarget gain sequence less than when ducking during playback from thefirst app type.

11. The method of statement 10 wherein the first app type includes game,music, or movie.

12. The method of statement 10 wherein the second app type includespodcast app or web browser.

13. A method for dynamic playback of target sound, the methodcomprising: generating a target sound sequence in accordance with a usersetting; driving a speaker with the target sound sequence; and makingautomatic adjustments to the target sound sequence as a function of thetime day or as a function of ambient environment light levels.

14. The method of statement 13 wherein making automatic adjustmentscomprises adjusting the target sound sequence to produce brighter soundin the morning or during daylight, than in the evening or at night time.

15. A non-transitory computer readable medium comprising instructionsthat configure a processor to perform the method in any of thestatements 1-14.

16. The computer readable medium of statement 15 as integrated into asmartphone, a smartwatch, a laptop computer, a tablet computer or adesktop computer.

17. The computer readable medium of anyone of statements 13-16 whereinthe speaker is integrated in a housing of a headphone.

18. The computer readable medium of any one of statements 17 asintegrated into the housing of the headphone.

While certain aspects have been described above and shown in theaccompanying drawings, it is to be understood that such are merelyillustrative of and not restrictive on the broad invention, and that theinvention is not limited to the specific constructions and arrangementsshown and described, since various other modifications may occur tothose of ordinary skill in the art. For example, although thedescription above refers to a method whose operations may be performedby the processor 7 which may be integrated within the control device 2together with the memory 6, some if not all of those method operationscould alternatively be performed by a processor that is integratedwithin the headphone 3 (assuming the headphone has sufficient digitalcomputing and communication resources to do so.) The description is thusto be regarded as illustrative instead of limiting.

1. A method for playback of target sound, the method comprising:accessing at least part of a sound file as a plurality of bins, each binstoring a plurality of audio sections, wherein the plurality of audiosections is recorded nature sounds being rainfall sounds, and all of thesections in a first one of the bins have rainfall intensities that arelower than the rainfall intensities of all the sections in a second oneof the bins; selecting a plurality of selected audio sections from theplurality of bins and mixing the selected audio sections while crossfading to form a target sound sequence; and driving a speaker with thetarget sound sequence.
 2. The method of claim 1 wherein the selectedaudio sections are selected randomly from each bin.
 3. The method ofclaim 2 wherein for any given bin all of the sections in the given binsound different but have similar rainfall intensity.
 4. (canceled) 5.The method of claim 1 wherein the target sound sequence begins aprogression from low intensity rainfall and then intensifies over timeto high intensity rainfall, and wherein each time the target soundsequence starts playback, the progression from low intensity rainfall tohigh intensity rainfall has a different speed.
 6. The method of claim 1wherein selecting audio sections from the bins is in accordance with apredefined bin sequence from which the audio selections are made, thepredefined bin sequence repeats in order to continuously form the targetsound sequence, and when each section in a bin has been randomlyselected at least once the sections of the bin are shuffled before beingre-used in the predefined bin sequence.
 7. The method of claim 1 furthercomprising stereo widening the target sound sequence into a leftheadphone driver signal and a right headphone driver signal.
 8. Themethod of claim 1 further comprising downloading the plurality bins ofthe sound file from a cloud server into a headphone in which the speakeris integrated, or into a control device that is communicatively coupledto the headphone.
 9. A non-transitory computer readable mediumcomprising instructions that configure a processor to: access at leastpart of a sound file as a plurality of bins, each bin storing aplurality of audio sections, wherein the plurality of audio sections isrecorded nature sounds being rainfall sounds; and select audio sectionsfrom the plurality of bins and mix the selected audio sections whilecross fading to form a target sound sequence, wherein the target soundsequence is to then drive a speaker, and wherein the target soundsequence begins a progression from low intensity rainfall and thenintensifies over time to high intensity rainfall, and each time thetarget sound sequence starts playback the progression from low intensityrainfall to high intensity rainfall has a different speed.
 10. Thecomputer readable medium of claim 9 wherein the selected audio sectionsare selected randomly from each bin.
 11. The computer readable medium ofclaim 10 wherein for any given bin all of the sections in the given binsound different but have similar rainfall intensity.
 12. The computerreadable medium of claim 10 wherein all of the sections in a first oneof the bins have rainfall intensities that are lower than the rainfallintensities of all the sections in a second one of the bins. 13.(canceled)
 14. The computer readable medium of claim 9 wherein selectingaudio sections from the bins is in accordance with a predefined binsequence from which the audio selections are made, the predefined binsequence repeats in order to continuously form the target soundsequence, and when each section in a bin has been randomly selected atleast once the sections of the bin are shuffled before being re-used inthe predefined bin sequence.
 15. The computer readable medium of claim 9wherein the processor is further configured to stereo widen the targetsound sequence into a left headphone driver signal and a right headphonedriver signal.
 16. The computer readable medium of claim 9 wherein theprocessor is further configured to download the plurality bins of thesound file from a cloud server into a headphone in which the speaker isintegrated, or into a control device that is communicatively coupled tothe headphone.
 17. The computer readable medium of claim 16 asintegrated into the control device along with the processor.
 18. Thecomputer readable medium of claim 17 wherein the control device is asmartphone, a smartwatch, a laptop computer, a tablet computer or adesktop computer.
 19. The computer readable medium of claim 16 asintegrated into the housing of the headphone along with the processor.20. An audio device comprising: a processor; and memory having storedtherein instructions that configure the processor to access at leastpart of a sound file as a plurality of bins, each bin storing aplurality of audio sections, wherein the plurality of audio sections isrecorded nature sounds being rainfall sounds; and select audio sectionsfrom the plurality of bins and mix the selected audio sections whilecross fading to form a target sound sequence, wherein the audio sectionsare selected from the plurality of bins in accordance with a predefinedbin sequence, the predefined bin sequence repeats in order tocontinuously form the target sound sequence, and when each section in abin has been randomly selected at least once the sections of the bin areshuffled before being re-used in the predefined bin sequence, andwherein the target sound sequence is to then drive a speaker.
 21. Theaudio device of claim 20 wherein the processor is further configured tostereo widen the target sound sequence into a left headphone driversignal and a right headphone driver signal.
 22. The audio device ofclaim 20 wherein the sound file is stored in the memory.
 23. The audiodevice of claim 20 wherein the processor and the memory are integratedin a smartphone, a smartwatch, a laptop computer, a tablet computer or adesktop computer.